Clicking Print opens a small pop-up window and loads the labels into it; the printable page inside that window is set to the paper size of the label size you selected (e.g. 8.5 x 11 in for Avery sheets, 4 x 2 in for thermal), which most browsers use to preselect that paper size in the print dialog. Allow pop-ups for your Sprwt admin site if nothing opens. In your browser's print dialog, confirm the matching paper size, set margins to none and scale to 100% - do not use "fit to page". For the thermal sizes (marked Beta) select the roll printer and its label size. If labels are offset on Avery sheets, adjust Column you want to start and Row you want to start only for skipped positions; alignment itself is fixed by the template.